1. Technical Field
The present invention relates generally to security systems for digital recordings, and more particularly relates to anti-pirating schemes for controlling the copying, playing, and distribution of digital music.
2. Related Art
The popularity of both the Internet and digital media technologies (e.g., compact disks “CD's” and digital versatile disks “DVD's”) has created tremendous problems for copyright owners of digital media content. The ability to reproduce, play and transmit digital content has become readily available to anyone with a personal computer and access to the Internet. This ability has led to widespread abuses to the rights of copyright owners who are unable to stop the illegal reproduction of their works.
One particular area where copyright ownership is particularly abused involves the music industry. The illicit pirating of digital music across the Internet is causing immeasurable damages to the music industry. Heretofore, most music content has been packaged and stored in an open, unsecured format that can be read and processed by any digital media player or recorder, i.e., content can be readily reproduced, stored and transmitted. To address this, the music industry has sought to create a secure domain to control the rampant pirating of music.
One solution the music industry is exploring involves establishing standards for secure playback and recording devices that process specially encoded content. Numerous secure devices and systems have been proposed. For instance, U.S. Pat. No. 5,513,260, issued on Apr. 30, 1996, entitled, Method and Apparatus For Copy Protection For Various Recording Media, describes a system in which an authorization signature is required before a protected CD can be played. PCT application WO 99/60568, published on Nov. 25, 1999, entitled, Copy Protection Using Broken Modulation Rules, also discloses various anti-pirating systems. Each of these references is hereby incorporated by reference.
In addition, a group referred to as SDMI (Secure Digital Music Initiative), made up of more than 180 companies and organizations representing information technology, consumer electronics, telecommunication, security technology, the worldwide recording industry, and Internet service providers, is attempting to develop standards and architectures for secure delivery of digital music in all forms. Information regarding SDMI can be found at their website at <www.sdmi.org>.
One of the challenges with implementing compliant systems, such as those sought under SDMI, is that various competing requirements must be met. For instance, under SDMI: (1) people must be allowed to make an unlimited number of personal copies of their CDs if in possession of the original CD; (2) SDMI-compliant players must be able to play music already in a library; (3) SDMI must provide the ability to prevent large numbers of perfect digital copies of music; and (4) SDMI must prevent the distribution on the Internet without any compensation to the creator or copyright holder. Thus, SDMI requires that a limited form of copying must be allowed, while at the same time widespread copying must be prohibited.
Unfortunately, such competing requirements create opportunities for hackers and pirates to defeat the protection schemes of the systems. Accordingly, protection schemes that are difficult to defeat, but will meet the open requirements for initiatives such as SDMI, must be developed.